I've been lucky in the last two hurricane events (20004/5 and 2017) in that the city water has not been disrupted...it does make the heat more tolerable with the ability to take a shower, even though it is a little cool...

I have an existing shallow well casing, which I retro fitted a deep piston pump several years ago... I do store about 20gal in 2 Scepter cans and 2 Aqua Tainers (one of which is at least 20 years old... I add a couple of milliliters of clorox when I change out the water, which I try to do at the beginning of at least every other season, or when a projected track is forecast

for Irma, the case of bottled water was sufficient...an insulated cooler mug was a pleasant addition so at least cool ice tea was available